Research On Evolution Of Urban Lakes In Wuhan Based On RS/GIS

Hubei is called as "The Province with Thousands of Lakes" in China, and Wuhan has the name of "The City with Hundreds of Lakes". It is the rivers and lakes that have bred up people of Wuhan for generations. Unfortunately, urban lakes have fallen into an awkward situation with the rapid development of urbanization and sharp increase of urban population in recently years. The numbers and areas of urban lake have sharply decreased; some urban lakes have deposited; some became swamp. Additionally, soil erosion caused by human factors has shoaled lakes and reduced reservoir capacity. Trade-waste sewage and domestic sewage flow into lakes, which has caused the deterioration of water quality.Based on background described above, the spatial information of urban lakes is acquired in the thesis acquires with remote sensing technique and data collection, analysis, processing and output provided by GIS, the spatial evolution of urban lakes in Wuhan during the last two decades is studied, and dynamic mechanism at the point of urban planning is analyzed. The purpose of research and analysis is to provide theoretic foundations for the comprehensive management, protection and exploitation of urban lakes, and to provide decision-making support for urban development and management.First of all in this paper, the definition of lake is described, the traditional functions of lakes and accessional functions of urban lakes are then discussed; the development of researches in China on lake science is reviewed also, and current status of lake research in the worldwide is summarized. Secondly, based on SPOT satellite and QuickBird images, the processing of digital images is discussed, the spatial information of urban lakes in 1986,1995,2000,2002 by computer classification and image visual interpretation is acquired, and the spatial evolution of urban lakes is quantitatively analyzed. Thirdly, the dynamic mechanism from such four aspects: urban population, economic development, urbanization and lake management is studied. Finally, conclusions on lake evolution and its dynamic mechanism obtained, the countermeasure is also pointed out and suggestions are made on the future urban lake protection.